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Chemistry at the Vatican

The new Pope, Francis, we now learn, has a degree in Chemistry.

The new Pope, Francis, we now learn, has a degree in Chemistry. He received a Master’s from the University of Buenos Aires.  It is interesting then to note that his selection was signaled through some nifty chemistry. The smoke signals used during the conclave are either black, to indicate that the cardinals have failed to elect a pope, or white if they have been successful.  The smoke is produced by burning the ballots used in the voting. In the 2005 conclave there was some confusion as to the color of the smoke that emerged after Pope Benedict was elected. The person on the roof of St Peter’s Basilica, who was supposed to ring the great bell to accompany the positive smoke signal, waited for more than 15 minutes because he was not sure of the color. This time there was no confusion. There were two stoves installed in the Sistine Chapel, both attached to a single copper flue leading up to the roof. One, made of cast iron was used to burn the cardinals' ballots as in the past. The second stove was designed to ignite flares electronically which, depending on their composition, sent out either white or black smoke. The black smoke was produced by a mixture of potassium perchlorate, sulfur and anthracene, a chemical found in coal tar. The white smoke on the other hand was derived from a mixture of potassium chlorate, lactose, and some pine resin known as Greek pitch. To improve the draught, the flue was pre-heated with electric current and equipped with a fan to whisk the smoke upwards. Another example of chemistry as the “central science!”

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